The Democratic Progressive Party (DPP) is a centre-left Taiwanese nationalist political party in Taiwan. As the dominant party in the Pan-Green Coalition, one of the two main political camps in Taiwan, the DPP is currently the ruling party in Taiwan, leading a minority government that controls the presidency and the central government.

Founded in 1986 by Hsu Hsin-liang, Roger Hsieh and Lin Shui-chuan, a year prior to the end of martial law, the DPP is one of two major parties in Taiwan, the other being the Kuomintang (KMT), a Chinese nationalist party previously ruling the country as a one-party state, and its smaller allies in the Pan-Blue Coalition. It has traditionally been associated with a strong advocacy of human rights, emerging against the authoritarian White Terror that was initiated by the KMT, as well as the promotion of Taiwanese nationalism and identity. Lai Ching-te is the current chairperson of the DPP from 2023, who also serves as the incumbent President and is the third member of the DPP to hold the presidency; he succeeded fellow DPP member Tsai Ing-wen in May 2024.

The DPP is a longtime member of Liberal International and a founding member of the Council of Asian Liberals and Democrats. It represented Taiwan in the Unrepresented Nations and Peoples Organization (UNPO). The DPP is widely classified as socially liberal, having been founded as a party for human rights, including factions within the party supporting same-sex marriage and other LGBT rights. On foreign policy, the DPP is more willing to increase military expenditures to prevent military intimidation from the People's Republic of China (PRC) owing to the ambiguous political status of Taiwan. It favors closer ties with democratic nations such as Japan and the United States, as well as the nations of ASEAN as part of its New Southbound Policy.

In its policy on cross-strait relations, the DPP as a ruling party chooses to keep the status quo of Taiwan, instead of approaching de jure independence, despite being a pro-independence group in its party platform. The party considers that Taiwan is already a sovereign country under the name "Republic of China" and not subordinate to the PRC. The DPP is frequently accused by the PRC government of being a primary force in Taiwan to "prevent the Chinese nation from achieving complete reunification" and "halt the process of national rejuvenation" due to the party's outspoken advocacy of the Taiwanese nationalism, Taiwanese self-determination, and its firm opposition to "One China", including the alleged "1992 Consensus" narratives by both the PRC and the KMT.

The DPP's roots were in the Tangwai movement, which formed in opposition to the Kuomintang's one-party authoritarian rule under the "party-state" system during martial law. This movement culminated in the formation of the DPP as an alternative, but still illegal, party on 28 September 1986 by eighteen organizing members at Grand Hotel Taipei, with a total of 132 people joining the party in attendance. The new party members contested the 1986 election as "nonpartisan" candidates since competing parties would remain illegal until the following year. These early members of the party, like the tangwai, drew heavily from the ranks of family members and defense lawyers of political prisoners, as well as intellectuals and artists who had spent time abroad. These individuals were strongly committed to political change toward democracy and freedom of speech, press, assembly, and association.

The tangwai were not a unified political unit and consisted of factions which carried over into the early DPP. At its founding the DPP consisted of three factions: the Kang group, a moderate faction led by Kang Ning-hsiang, New Tide faction, consisting of intellectuals and social activists led by Wu Nai-ren and Chiou I-jen, and the Progress Faction led by Lin Cheng-chieh, a waishengren opposed to independence. Moderates would later coalesce around the Formosa faction, founded by those arrested during the Formosa Incident after their release from prison. In the early days of the party, the Formosa faction focused on winning elections by wielding the star power of its leaders, while New Tide would focus on ideological mobilization and developing grassroots support for social movements. As a result, the Formosa faction would become more moderate, often bending to public opinion, while New Tide would become more ideologically cohesive. By 1988 the Formosa Faction would dominate high-level positions within the party.

The party did not at the outset give explicit support to an independent Taiwanese national identity, partially because moderates such as Hsu Hsin-liang were concerned that such a move that could have invited a violent crackdown by the Kuomintang and alienate voters, but also because some members such as Lin Cheng-chieh supported unification. Partially due to their waning influence within the party and partially due to their ideological commitment, between 1988 and 1991 the New Tide Faction would push the independence issue, bolstered by the return of pro-independence activists from overseas who were previously barred from Taiwan. In 1991, in order to head off the New Tide, party chairman Hsu Hsin-liang of the moderate Formosa faction agreed to include language in the party charter which advocated for the drafting of a new constitution as well as declaration of a new Republic of Taiwan via referendum (which resulted in many pro-unification members leaving the party). However, the party would quickly begin to walk back on this language, and eventually in 1999 the party congress passed a resolution that Taiwan was already an independent country, under the official name "Republic of China", and that any constitutional changes should be approved by the people via referendum, while emphasizing the use of the name "Taiwan" in international settings.

Despite its lack of electoral success, the pressure that the DPP created on the ruling KMT via its demands are widely credited in the political reforms of the 1990s, most notably the direct popular election of Republic of China's president and all representatives in the National Assembly and Legislative Yuan, as well as the ability to openly discuss events from the past such as the February 28 Incident and its long aftermath of martial law, and space for a greater variety of political views and advocacy. Once the DPP had representation in the Legislative Yuan, the party used the legislature as a forum to challenge the ruling KMT.